Wheeze and urban variation in South Asia.

ABSTRACT

Typically, urban South Asia is characterised by narrow streets, heavy traffic, visible haze, unplanned city architecture and the use of kerosene or wood-burning stoves at home. However, some urban areas in South Asia are clean and modern, with concrete housing, vehicle emission regulations and use of smoke-free household fuel. The purpose of this study was to compare wheeze prevalence in 13-14-year-olds between two South Asian cities (Galle, Chandigarh), representing each of the above two archetypes. The validated one-page International Study on Asthma and Allergies in Childhood (ISAAC) questionnaire for 13-14-year-olds was used for the study. Of 1814 distributed questionnaires, 1737 (95.8%) were completed correctly and returned (Galle n=1162; Chandigarh n=575). Crude prevalence rates, and prevalence odds ratios (with 95% two-sided confidence intervals (CI) for comparison of prevalence rates), were calculated. The prevalence rate for wheezing in Galle (28.7%) was higher than in Chandigarh (12.5%). The prevalence odds ratios (Galle versus Chandigarh) for lifetime wheezing (2.3; 1.8-2.9), wheezing in the previous year (2.1; 1.6-2.7), exercise-related wheeze (4.8; 3.5-6.7) and physician-diagnosed wheeze (1.7; 1.2-2.3) demonstrated significant differences in wheeze prevalence between the two cities ( P<0.05). The numbers of 13-14-year-olds experiencing less than 12 wheezing episodes per year or sleep disturbance due to wheeze of less than 1 night per week were also significantly higher for Galle than Chandigarh. There is a higher prevalence of wheeze in 13-14-year-old children living in an old-fashioned, congested city than in a clean and modern city in South Asia.